This application is a proposal to serve as the Statistical and Data Management Center of the International Maternal Pediatric Adolescent AIDS Clinical Trials Group (IMPAACT), in affiliation with the IMPAACT Leadership Group headed by Dr. J. Brooks Jackson (JHU). IMPAACT is proposing a therapeutic research agenda to address objectives in the NIAID high priority research areas of Prevention of Mother-to-Child Transmission of HIV Infection; Translational Research/Drug Development; Optimization of Clinical Management; and Vaccine Research and Development. The Specific Aims are to support the research agenda of IMPAACT by providing a group of highly experienced statisticians, data managers and other professionals who are knowledgeable in all aspects of HIV therapeutic research and an organizational structure that promotes this work with IMPAACT; to provide expertise and high quality clinical and laboratory data management and communications systems to support the development, conduct, and analysis of IMPAACT studies; and to advance the mission of IMPAACT through innovation in study design and analysis, providing leadership in cross-study analyses and collaborating effectively with other HIV Trials Networks and HIV research organizations.